Art of and means for making sound producing articles



Dec. 1l, 1934. J; B` HA-wLEY 1,984,018

ART orun' mms PoR MAKING sourmv nonuclue ARTICLES Filed July 20, 1931!.l

y 40 ing after article is completed, will be smoother Patented Deo. 1l, 1934 I UNITEDSTATES PATENT OFFICE Lemma ABT F AND BIEANSv FOB MAKING SOUND PBODUCING ARTICLES vJesse B. Hawley, Geneva, lll.

Application July zo, 1931, serai No, 551,965

'1 claims. (ci. sz-s'z) The present invention relates to the making ing or forming means for carrying out the invenor producing of sound producing members or tion;

the like, particularly those of the fibrous kind. Fig, 2 isaseetional view of astripplng die;

Among the objects of the i'nventionA is to pro- Fig3 is 9, similar view of a drying die; and, 5 vide a novel sound producing member or article, Fig, 4 is a. similar viewrof the blank-produced 5 preferably of the diaphragmatic type. A speciilc by the invention. illustrative embodiment of it is shown as conical The diaphragm is preferably made from iibrous or conic inform. It is composed of material, material, such as pulp. The pulp is usually repreferably moldable, accretable, and integratable ceived in the form of dry sheets, and tor the purbrous material, having water or moisture proofposes of carrying out the process of this invenl0 ing characteristics or properties. I1' the diation, are placed with water in a beater ior beater phragm be iirst made oi fibrous material, and enginey to beat the pulp and to disinte ate and then, after drying. it be ated and impregnated disperse the ilbres in the water, and also to with proong substances, the diaphragm becomes shorten and hydrate the flbresto the desired point l5 loaded, whereby it possesses inertia to free moveer extent l5 ment of the diaphragm when vibrated to propa- The mixture or batch is then treated to proo gate or generate sound. The-impregnation is not the nbres. This may be effected in any or several thorough nor uniform, and some parts of the ways, As for example, while ontinuing the treated diaphragm will be affected by climatic beating of the material in the beater engine, conditions. water-prooilng wax. may be added to the mixture, 20

One of the purposes 0fths invention lis t0 as in the proportions of about from one to eight avoid the disadvantages mentioned, by rst per cent of the weight of the dry pulp iirst placed proofing the material before it is molded, formed, in the beater, The beating and stirring may con-V aeereted, integrated, and United 1111011 e nvel tinue for a suicient period of time, such as from POI'OUS fermer e about ten to fifteen minutes until the wax has 25 Another object of the invention is to provide been thoroughly dispersed and mixed, after which a novel method or process for making such novel pdwdered alum may be added in 9, quantity sumdeviee whereby the device Will be iight in Weight cient to set the wax on the ilbres. The beating so as to have little inertia and momentum, will and stirring may continue until the setting has be dense and still in given parts, Such aS the been eiected, and then the material, termed 30 vibratile part;will be more rapidly produced by stock, may be stored in a suitable tank or vat simpler operations end at less expense and cost for use when molding on the. porous rormers. than heretofore, will be produced on an increased As another example, the proofing may be efeapaeity 0f prOdueiiOn, Willbe dried more quickly" fected by the same or a similar process, with will be more accurately and uniformly made, paper-makers rosin which may be set with alum35 may be compressed as desired, Will have sharper as in the case of the wax. The amount of rosin or more distinct features, as angles and the like, used may be'about from one t0 five per cent of will eliminate treatments heretofore necessary the weight of the dry pulp drst plneed in the to provide stillness in given parts, as also proofbeaten Proofing may also be eilected by the same or a 40 and have a better appearance so that it may be similar process with latex which may also be Set exposed, will be susceptible to decoration for r rosln.

esthetic effects, if desired, and will produce sound wlshplgs mvoigisg produced by with a rendition true to the original sound being the same or similar process by mixing in emulsireproduced by the diaphragm n d halt d t with the alum as in the cases 45 The invention also comprehends, as an object o: wp rosmananemtex thereof, a novel means or device for carrying out' the novel process, and for producing the A5 further examples m0011113 may likewise by novel means of this invention, a like or a simllarprocess, be effected with starch,

A fother objects, capabiuues, advantages, fee.- 0r with silicate 0f sode. Setting with alum is s0 tures, and process steps are comprehended by the not necessary-1n these eases.

invention as will later appear and as are inher-- The latex,.aspha1t, silicate of soda, and starch ently possessed thereby. Y vary or change the' acoustic properties or char- Referring to the drawing: acteristics of the diaphragm. and hence they may Fig. 1l is a transverse sectional view oi a moldbe varied or even combined two or more o! them .155,

in predetermined proportions, so as to obtain the desired acoustic effects in the final article.

The ability of proong varies in degree from higher to lower in the order of asphalt, wax, latex,

rosin and alum, starch, and silicate of soda.

It is to be understood, when desired, any two or more of these proofing substances also may be combined to obtain any degree of proofing with the acoustic property desired in the dia phragm.

The process may be practiced in diierent ways, and preferably by use of a novel porous former, an illustrative embodiment of which is herein described. This former may rest upon a table 1 supported by suitable means for raising and lowering the table and the members supported thereby, in and out of the bath of atank 2.

Upon the table 1 is a former member 3 provided with apertures 4 running from grooves 5 formed on the surface of the vmember 3. The edge or border portion of the member 3 is provided with a flange 6 adapted to rest on the table l, and hold the body portion of the member 3 spaced above the table 1 so as to define a chamber 7 which may act as a suction chamber.

Upon the ridges 8 of the member 3 is supported a former member 9 of thin material, such as sheet metal, Celluloid, rubber, or compositions of various sorts, this member 9 being provided with innumerable apertures, or pores 10 for the passage of the water of the bath.

The members 3 and 9 shown, are shaped or contouredfor the making of a diaphragmatic blank of conic type. Accordingly, using member 9 as an example, this member as a conic portion 11, a plano-border portion 12, an undulated juncture portion 13, an apical cylindric portion 14, and a cap 15. The member 3 has correspondingly shaped portions, as shown.

Beneath the member 3 and in the chamber 7 is located a blanking member in the form of suction cup 16 the rim 17 of which is adapted to engage the under surface of the conic portion of the member 3, to blank off a part of the former, as shown in the drawing. The cup has at its bottom a suction and drain duct 18 suitably connected to a suction source (not shown), this duct being slidable in ,the apertured boss 19 of the table 1, as is clearly shown in the drawing.

In operation, the former and table are lowered in thetank 2 to submerge them in a bath, and with the suction cup in contact with the member 9 and in the position shown in full lines in the drawing, and with the suction effective in the cup 16 and duct 18, a stratum 20 of proofed fibrous material is deposited, accreted, integrated, and knitted upon the part of the former above the cup 16. The remainder of the former is this blanked ot. The suction draws the water of the bath through the pores 4, grooves 5, holes 10, and thence through duct 18, the fibres thus being deposited on the member 9 and held mata ter thereon by the suction.

Completion of the blank by deposit upon the formed stratum 20, and integrating uniting, and

knitting therewith, whereby an unitary integral.y unit or blank is formed, with the apical part thicker than the remainder of the blank, to give stiffness tothe vibratile or conic portion of the sound producing member.l

If completion is to be effected from another bath, with the suction still acting, the device is raised out of the bath, and then submerged into the other bath, while at the same time the cup is lowered to the dotted line position shown in the drawing, so as to cause the suction to be eiective throughout the chamber 7, and a deposition, accretion, integration, and knitting of the stratum 21 over the remainder of the former and the stratum 20, as also an integration, knitting and uniting with the stratum 20 to produce an unitary integral unit or blank, with a thicker and stiffer apical part for the vibratile portion of the sound producing member.

If desired the depositing of the strata may be conversely eifected, in which case, when the former is first submerged, the cup will be lowered to the dotted line position in the drawings so to cause the formation of a stratum of accreted and integrated brous material over the wholer of the former, and then, the cup may be raised to contact the former and thus blank-01T a portion of it, whereby a further or other deposit in the `form of a stratum may be accreted, integrated, united and knitted with the apical portion of the previously formed stratum. The blank thus obtained may then be treated and operated upon as herein otherwise described.

After thus completing the blank, the device is then raised out of the bath, with the suction still acting to drain off residual water. Then a female suction die or box 22 is placed over the blank, with the suction shut-olf or reversed in the chamber 7, and with suction eiective in die 22, the blank is stripped 'from the former 3 9, and engaged with the contoured surface 23 conforming with the shape of the blank, the contoured wall 23 having a number of apertures 24 for the suction of air for engaging and holding the blank with and to the contoured surface 23. The die 22 has connected to it a suction duct 25. Its contoured surface acts as a die to uniformly distinctly shape the wet blanks.

For the purpose of drying the blank, and also for pressing it, a hot male die 26 having a contoured surface 27 conforming to the form of the blank, is pressed against the blank. This die is heated so as to have a temperature of from 500 to 800 F. Itis pressed against the blank held in the die 22, if a smooth surfaced blank is desired, but if a fluiy surface condition is preferred, the die is not pressed against the blank but is merely held in contact with it.

The temperature of the die is such as to rapidly I convert the water or moisture in the blank into steam, vapor and the like, which are drawn out by the suction in the die 22. When the blank is dry, the die `is removed, and the suction in the die 22 reversed to pressure to blow-off the blank.

The blank is then placed in a press having dies to compress and limber the juncture 13a of the blank. Then the top l5'd is cut-o to leave the cylindrical portion 14a for the winding thereon of the voice coil. If desired the apical part 20a may be compressed to the same thickness as the remainder of the blank, so that the apical part may be denser and stiffer. This compres1 sion may be effected during the drying or after,

as desired. The conical part with the juncture 13* and a portion of the border part 10, constitute the vibratile part of the diaphragm, while the remainder of the border part 10* acts as the supporting portion of the diaphragm.

When drying with the female and male dies. great accuracy and uniformity of shape and form of the ilnal dried unit or,blank are obtained. with distinct curves, angles, etc., all of which are uniform for all blanks.

By the above disclosed process and means'there is no need of iirst drying the blank in a heater or oven, and then die pressing the dried blank, but the drying and die pressing are effected in ya step when the blank is made and take the distinct shape and form desired without distortions and strains that occur when die pressing an object in already dried condition. Moreover, the use of a screen or like reticulated former element is avoided, since the former member 9 is of thin sheet materialand provided with a very large number of small apertures or pores. This provides for a more uniform andsmoother blank which may be thinner and lighter in weight than one made with a screen and having projections which are formed in the comparatively larger holes of the screen.

This invention also eliminates the treatments with chemicals, such as lacquers and the like by way of coating, impregnating and the like with attendant lack of uniformity and thoroughness of treatment. The proofing in that way, that is, after completion of the blank, is eliminated with its disadvantages. Pre-proong produces a better result than by post-impregnation. Preprooilng adds much less weight to the diaphragm, and avoids the inertia of the loading material when vibrating the diaphragm. By the present invention the diaphragm is lighter in weight, stiffer at the apical part, and more supple at the juncture and supporting border portion.

While VI have herein described and on the drawing shown an illustrative embodiment and mode of using and carrying out the invention,` it is to be understood that the invention is not limited thereto but comprehends other means, process steps, modes of operation and; treatment, structures, arrangement of parts, details, and features lwithout departing from 'the spirit oi the invention.

Having thus disclosed the invention, I claimgw' 1. In a process of making sound producing articles, the step of producing a predetermined portion of the article by forming a stratum of fibrous material upon acoextensive portion of a porous former while said former is at rest, and completing the article by forming a stratum of ilbrous .material upon the'entire area of said former including the uncoated area thereof and integrating it upon the nrst mentioned stratum while the former is at rest.

2. In a process ofmaking sound producing articles from fibrous materials, the step of producing a portion of the article by applying suction to a selected part of the area-oi a foraminous screen while it is submerged in a pulp bath, and completing the article by; applying suction to approximately the entire area of said screen while it is similarly submerged.

3. In a process of making sound producing articles, the step of producing a predetermined portion of the article by forming a stratum of nbrous material upon a coextensive portion of a porous former while said former is at rest, completing the article by forming a stratum ot fibrous material upon the entire area of said former including the uncoated area thereof and integrating it upon the first mentioned stratum while the former is at rest, and compacting the integrated strata.

4. In a process of making sound producing articles from nbrous materials, the step of producing a portion of the` article by applying suction to a selected part of the area of a foraminous screen while it is submerged in a pulp bath, completing the article by applying suction to approximately the entire area of said screen while it is similarly submerged, and then applyin suction to said strata in the opposite direction.

5. In aprooess of making sound producing articles from fibrous materials, the step of producing a portion of the article by applying suction to a selected part of the area of a foraminous screen while it is submerged in a pulp bath, completing the article by applying suction to approximately the entire area of said screen while it is similarly submerged, drying the body, and applying suction to the body in the opposite direction during the drying stage.

6. `A former lfor making iibrous articles comprising a porous former body having a contoured surface for accretion and integration thereon of fibrous material, and a hollow suction member cooperating with said former body, said member being adjustable toward and from the former' body and so constructed and arranged as to effect fractional accretion and integration of fibrous material on said former body in accordance with its position with respect thereto.

7. A former for making fibrous articles comprising a porous former body having acontoured A surface for accretionand integration thereon of fibrous material, and a hollow suction member of inverted conical shape cooperating with said yi'ormer body, said member being adjustable toward and from the former body and so constructed and arranged as to effect fractional accretion and integration of nbrous material on said member in accordance with the position oi its open end with respect thereto.

.masa B. 

